Most of the plants possess this specialized structure. However, root cap is absent in some aquatic and parasitic plants. In such cases, a sac-like structure called the root pocket may form instead.
Structure
Function
Formation
A new root cap cell layer is formed via periclinal division of proximal stem cells present in apical meristematic region. Periclinal division involves the division of cells parallel to the plane of division. On the other hand, the oldest cell layer at the outermost position, the peripheral cell, disintegrates. By this process, the older cell layer gets detached at a constant interval while they are still alive. Due to this continuous autonomous process, the root cap constantly gets renewed. So, it is always composed of viable cells.
